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1.
The medicinal herb, lemon balm (Melissa officinalis L.), which is high in rosmarinic acid (RA), has well-known therapeutic value. The goals of this study were to investigate the effects of methyl jasmonate (MeJA) on RA content, total phenolic content (TPC), and total flavonoid content (TFC), as well as changes in expression of their biosynthesis-related key genes (MoPAL, Mo4CL, and MoRAS) in Iranian lemon balm ecotypes, as first reported. Our results revealed that MeJA doses significantly increase the RA content, TPC, and TFC in both ecotypes compared with the control samples. Additionally, the higher expression levels of MoPAL, Mo4CL, and MoRAS following treatment were linked to RA accumulation in all treatments for both Iranian lemon balm ecotypes. After 24 h of exposure to 150 µM MeJA concentration, HPLC analysis showed that MeJA significantly increased RA content in Esfahan and Ilam ecotypes, which was about 4.18- and 7.43-fold higher than untreated plants. Our findings suggested that MeJA has a considerable influence on RA, TPC, and TFC accumulation in MeJA-treated Iranian M. officinalis, which might be the result of gene activation from the phenylpropanoid pathway. As a result of our findings, we now have a better understanding of the molecular processes behind RA production in lemon balm plants.  相似文献   

2.
Structural and compositional features of whole cells of the plant-growth-promoting rhizobacterium Azospirillum brasilense Sp7 under standard and heavy metal-stressed conditions are analysed using Fourier transform infrared (FTIR) spectroscopy and compared with the FT-Raman spectroscopic data obtained previously [J. Mol. Struct. 563–564 (2001) 199]. The structural spectroscopic information is considered together with inductively coupled plasma-mass spectrometric (ICP-MS) analytical data on the content of the heavy metal cations (Co2+, Cu2+ and Zn2+) in the bacterial cells. As a bacterial response to heavy metal stress, all the three metals, being taken up by bacterial cells from the culture medium (0.2 mM) in significant amounts (ca. 0.12, 0.48 and 4.2 mg per gram of dry biomass for Co, Cu and Zn, respectively), are shown to induce essential metabolic changes in the bacterium revealed in the spectra, including the accumulation of polyester compounds in bacterial cells and their enhanced hydration affecting certain IR vibrational modes of functional groups involved.  相似文献   

3.
本文采用ICP-MS法测定了土壤国家标准样品中的部分重金属元素(Cd、Cu、Pb、Zn、Cr、 Ni、Mo)的含量,其测定值与推荐值相符,准确度符合要求。各元素方法的检出限满足要求,精密度介于0.91%~4.34%,加标回收率介于94%~106%。该方法简便快速,结果准确,可以运用于大批量地质样品中的部分重金属元素含量的同时测定。  相似文献   

4.
外源钕减轻了重金属镉对菹草的毒害作用   总被引:8,自引:1,他引:8  
研究了不同浓度钕对菹草镉胁迫的缓解效应.结果表明,单一镉(10 mg·L-1)处理降低了菹草叶片抗氧化酶系超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)活性,丙二醛(MDA)含量升高,可溶性蛋白和叶绿素含量下降.用不同浓度钕处理后,明显减轻了这些症状,抗氧化酶活性均有所提高,与毒害对照相比,SOD、CAT及POD活性分别提高了14.0%~30.0%,8.8%~47.3%,4.6%~15.1%,并减轻了叶绿素和可溶性蛋白的降解,减缓了MDA的积累.随着钕浓度的进一步加大,缓解效应逐渐减弱,钕作用的最适浓度为10~15mg·L-1.  相似文献   

5.
建立了使用电感耦合等离子体-质谱仪技术(ICP-MS)分析硅胶奶嘴中锰、镍、铜、锌、镉、铅、铬、砷溶出量的方法.应用碰撞反应界面技术(CRI)有效地消除了多原子或离子对待测金属离子的干扰;选用89 Y,115In和209Bi等元素为内标混合液校正基体效应和信号漂移,确定了实验的最佳测定条件;研究了浸泡温度、浸泡时间以及浸泡提取方式对重金属溶出量的影响.该测试方法对于锰、镍、铜、锌、镉、铅、铬、砷的仪器检出限为0.01~2.00μg/L,仪器相对标准偏差为0.4%~2.8%,加标回收率为81.4%~113.1%.该方法快速、简便,具有较好的准确度和精密度,为硅胶奶嘴中重金属含量的监控提供了途径.  相似文献   

6.
青海歧穗大黄根部重金属元素特征   总被引:1,自引:0,他引:1  
为对比青海高原境内不同生境歧穗大黄中七种重金属元素特征,用原子吸收仪进行了分析测试.结果表明,青海歧穗大黄根部Pb元素含量具有随着海拔高度增加而降低的变化特征.  相似文献   

7.
川中丘陵区铁路旁土壤重金属含量及化学形态研究   总被引:3,自引:0,他引:3  
对川中丘陵区成昆铁路的三圣段、吴场段和成渝铁路的五凤段3个典型路段铁路沿线土壤重金属Cd、Zn、Cu、Pb含量及其化学形态进行了研究,并运用次生相富集系数法对重金属的潜在生态风险进行评估。结果表明:铁路沿线土壤重金属Cd、Zn、Cu、Pb含量与对照点相比都有不同程度的升高。Cd不仅具有高的含量,且化学形态主要为酸可交换态和可还原态,残渣态含量很低,其有效态比例>75%,具有很强的生物活性和可迁移性。Cu、Pb、Zn的化学形态则主要为残渣态,酸可交换态比例很小,但是Pb和Zn的可还原态和可氧化态比例较高,所以有效态比例也较高,分别为51.1%~54.9%和36.2%~50%。土壤重金属Cu在各典型路段的次生相富集系数为1.4~4.2;Zn在三圣段、吴场段2个典型路段的次生相富集系数超过3.0,均具有较大的潜在生态风险。  相似文献   

8.
北部湾文蛤体内氧化逆境标志物对重金属积累的响应研究   总被引:2,自引:0,他引:2  
研究目的是通过评价北部湾文蛤(Meretrix meretrix)体内7种氧化逆境标志物对重金属积累的响应, 筛选出能够灵敏指示海域现场重金属污染压力的生物标志物. 2011年秋季, 在北部湾沿海潮间带6个典型站位采集文蛤样品, 测定软组织中重金属含量及鳃、内脏中7种氧化逆境标志物水平, 分析其空间、组织分布特征, 然后对标志物水平与重金属含量进行相关性分析. 结果表明, 文蛤软组织中重金属积累量和氧化逆境标志物水平在站位间存在很大差异. 大多数氧化逆境标志物具有明显的组织差异性, 鳃中的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPx)、谷胱甘肽转硫酶(GST)活性以及还原型谷胱甘肽(GSH)、氧化型谷胱甘肽(GSSG)含量均高于内脏, 过氧化氢酶(CAT)在内脏中的活性较高, 而硫代巴比妥酸反应物(TBARs)在两组织中无明显的分布差异. 多种重金属共存的情况下, 鳃的GSH/GSSG与软组织Cd含量有显著相关性; 4种抗氧化酶中, 鳃CAT对Pb具有显著正响应, 内脏CAT、GST对As具有显著负响应. 鳃TBARs分别与Hg、Cd含量呈显著正相关、负相关, 内脏TBARs则与Pb含量呈负相关, 表明这些标志物能够灵敏指示重金属对文蛤抗氧化防御机能的影响, 适于作为评价北部湾重金属污染压力的指标.  相似文献   

9.
目前海洋沉积物前处理主要通过电热板消解,但该方法存在消解不完全、前处理时间长、重复性较差以及手工消解操作繁琐等问题。为提高海洋沉积物重金属消解效率,通过考察硝酸、盐酸、氢氟酸和高氯酸组合酸体系比例和最高消解温度对海洋沉积物预处理的影响,确定了最优的消解条件,建立了全自动消解-电感耦合等离子体质谱仪测定海洋沉积物中重金属的方法。结果显示硝酸占比越高各元素消解效果越好,盐酸用量不宜过多,逆王水消解比例最好。最优预处理条件为9 mL硝酸、3 mL盐酸、4 mL氢氟酸和2 mL高氯酸于160℃高温消解。该预处理条件下各元素相关性系数均大于0.999,经海洋沉积物标准样品(GBW07314)和实际样品应用,与国标法(GB/T 20260-2006)相比优化条件下各元素精密度和正确度均显著提高、检出限更低。各元素的相对标准偏差分别为0.9%~3.3%、0.5%~3.4%,回收率均在84.2%~102%。该方法自动化程度高、操作简便,可实现大批量样品预处理,适用于海洋沉积物中重金属元素的测定。  相似文献   

10.
The compounds containing transition metals orother heavy elements play important roles in chemistry.They possess diverse properties which have been util-ized in numerous functional materials. Some of theseproperties are also involved in biological processes.However, it is very difficult to study these compoundsdeeply by means of quantum chemical methods, be-cause in these systems usually there are a large amountof electrons, the distribution of the frontier orbitals isdense, the correlation be…  相似文献   

11.
离子印迹介孔材料具有吸附容量高、吸附选择性和骨架稳定等特点,在吸附分离领域有着广泛的应用前景。本文总结了目前离子印迹介孔材料的制备方法,阐述了分步合成法及一步合成法的各自特点;着重介绍了该材料在对重金属吸附和分离领域的研究与应用情况;简要说明了离子印迹介孔材料对重金属离子的吸附机理;并提出了离子印迹介孔材料在制备与应用中存在的问题。  相似文献   

12.
Plant growth-promoting rhizobacteria (PGPR) mediate heavy metal tolerance and improve phytoextraction potential in plants. The present research was conducted to find the potential of bacterial strains in improving the growth and phytoextraction abilities of Brassica nigra (L.) K. Koch. in chromium contaminated soil. In this study, a total of 15 bacterial strains were isolated from heavy metal polluted soil and were screened for their heavy metal tolerance and plant growth promotion potential. The most efficient strain was identified by 16S rRNA gene sequencing and was identified as Bacillus cereus. The isolate also showed the potential to solubilize phosphate and synthesize siderophore, phytohormones (indole acetic acid, cytokinin, and abscisic acid), and osmolyte (proline and sugar) in chromium (Cr+3) supplemented medium. The results of the present study showed that chromium stress has negative effects on seed germination and plant growth in B. nigra while inoculation of B. cereus improved plant growth and reduced chromium toxicity. The increase in seed germination percentage, shoot length, and root length was 28.07%, 35.86%, 19.11% while the fresh and dry biomass of the plant increased by 48.00% and 62.16%, respectively, as compared to the uninoculated/control plants. The photosynthetic pigments were also improved by bacterial inoculation as compared to untreated stress-exposed plants, i.e., increase in chlorophyll a, chlorophyll b, chlorophyll a + b, and carotenoid was d 25.94%, 10.65%, 20.35%, and 44.30%, respectively. Bacterial inoculation also resulted in osmotic adjustment (proline 8.76% and sugar 28.71%) and maintained the membrane stability (51.39%) which was also indicated by reduced malondialdehyde content (59.53% decrease). The antioxidant enzyme activities were also improved to 35.90% (superoxide dismutase), 59.61% (peroxide), and 33.33% (catalase) in inoculated stress-exposed plants as compared to the control plants. B. cereus inoculation also improved the uptake, bioaccumulation, and translocation of Cr in the plant. Data showed that B. cereus also increased Cr content in the root (2.71-fold) and shoot (4.01-fold), its bioaccumulation (2.71-fold in root and 4.03-fold in the shoot) and translocation (40%) was also high in B. nigra. The data revealed that B. cereus is a multifarious PGPR that efficiently tolerates heavy metal ions (Cr+3) and it can be used to enhance the growth and phytoextraction potential of B. nigra in heavy metal contaminated soil.  相似文献   

13.
海藻酸钠脱除重金属研究进展   总被引:1,自引:0,他引:1  
重金属污染已成为全球性的环境问题,脱除重金属是治理重金属污染的主要途径。海藻酸钠(SA)本身无毒、性质稳定、价格低廉,具有较强的胶凝性、成膜性和络合能力,既可作为脱除重金属的吸附材料,又可作为脱除重金属的固定化载体,在重金属脱除中具有广泛的应用。本文重点综述了SA凝胶球、SA复合膜、SA纳米复合材料、SA分子印迹脱除重金属,以及SA作为单一固定化载体和复合固定化载体脱除重金属进展情况。展望了SA脱除重金属的应用前景。  相似文献   

14.
GC-MS法在黔产宽叶缬草质控中的应用   总被引:2,自引:0,他引:2  
伍庆  余励  周宁  张明时  洪亮 《分析测试学报》2004,23(Z1):101-103
宽叶缬草(ValerianaofficinalisL.var.latifoliaMiq.)系败酱科植物。主产贵州,我国从东北至华北也有分布。具有镇静、镇痛、降压、解痉等作用。目前,对其挥发油研究较多,但采用气相色谱-质谱对药材质量进行研究较少。本文利用GC-MS,以水杨酸甲酯为内标,对药材中乙酸龙脑酯进行含量测定,建立其质量控制的方法。  相似文献   

15.
随着工业发展,土壤中累积的重金属对人类产生健康威胁。在全面评估土壤重金属污染的情况下,通过非传统稳定同位素测量可以对其来源进行有效解析。鉴于这一新兴领域的快速发展,对非传统稳定同位素在土壤重金属源解析中的作用进行了阐述。在此基础上,提出了现有的问题和展望,为土壤重金属污染源解析理论、技术的研究与应用提供借鉴,推进土壤重金属污染防控的建立与完善。  相似文献   

16.
In our study, Allium subhirsutum L. (AS) was investigated to assess its phenolic profile and bioactive molecules including flavonoids and organosulfur compounds. The antioxidant potential of AS and wound healing activity were addressed using skin wound healing and oxidative stress and inflammation marker estimation in rat models. Phytochemical and antiradical activities of AS extract (ASE) and oil (ASO) were studied. The rats were randomly assigned to four groups: group I served as a control and was treated with simple ointment base, group II was treated with ASE ointment, group III was treated with ASO ointment and group IV (reference group; Ref) was treated with a reference drug “Cytolcentella® cream”. Phytochemical screening showed that total phenols (215 ± 3.5 mg GAE/g) and flavonoids (172.4 ± 3.1 mg QE/g) were higher in the ASO than the ASE group. The results of the antioxidant properties showed that ASO exhibited the highest DPPH free radical scavenging potential (IC50 = 0.136 ± 0.07 mg/mL), FRAP test (IC50 = 0.013 ± 0.006 mg/mL), ABTS test (IC50 = 0.52 ± 0.03 mg/mL) and total antioxidant capacity (IC50 = 0.34 ± 0.06 mg/mL). In the wound healing study, topical application of ASO performed the fastest wound-repairing process estimated by a chromatic study, percentage wound closure, fibrinogen level and oxidative damage status, as compared to ASE, the Cytolcentella reference drug and the untreated rats. The use of AS extract and oil were also associated with the attenuation of oxidative stress damage in the wound-healing treated rats. Overall, the results provided that AS, particularly ASO, has a potential medicinal value to act as effective skin wound healing agent.  相似文献   

17.
Heavy metal ions are toxic, and their toxicities change with different valence states, charges, and radii. Among the methods used for heavy metal ion removal, adsorption is widely employed due to its low cost and simple operation. As natural anionic clays, layered double hydroxides (LDHs) have drawn considerable attention for their use in the removal of anionic pollutants (such as heavy metal anions) due to their high removal efficiency and environmental friendliness. This article reviews the effects of the charge, type, and radius of the cations in the laminates of LDHs and the anions in the LDH interlayers, as well as the charge and radius of the heavy metals and the conditions (such as pH, coexisting ions, and temperature) on removing heavy metal ions with LDHs. The removal mechanisms have also been discussed. LDHs are hugely promising as an application for removing heavy metal ions that exist in different ionic forms by controlling the type and condition of LDHs.  相似文献   

18.
Phytochemicals serve as potential therapeutic agents for the prevention and treatment of diseases. In this study, we elucidate the renoprotective activity of compounds isolated from Eucalyptus globulus and Melaleuca styphelioides extracts in glucose- and oxalate-challenged NRK-49F cell model. The antioxidant potential of isolated compounds was evaluated based on their effect on antioxidant enzyme activities and lipid peroxidation levels. The results demonstrated that exposure of NRK-49F cells to glucose and oxalate stress augmented cell damage and attenuated antioxidant enzyme activities. The phytochemicals 2,2,8-trimethyl-6-formyl-chrom-3-ene-7-O-β-D-glucopyranoside, Cornusiin B and tellimagrandin I treatment restored antioxidant enzyme activity, significantly lowered lipid peroxidation levels and effectively protected cells from glucose and oxalate stress equivalent to the known antioxidant, N-acetyl cysteine. Pterocarinin A significantly reversed cellular damage owing to glucose stress. In conclusion, the compounds isolated from E. globulus and M. styphelioides showed potential cytoprotective and anti-oxidative property against glucose- and oxalate-induced oxidative stress in NRK-49F cells.  相似文献   

19.
建立了自动消解仪-电感耦合等离子体发射光谱法(ICP-OES)同时测定水系沉积物中Cu、Zn、Ni、Cr、Pb、Co六种元素含量的方法。该方法的相关系数好、检出限低。方法经国家标准物质(GBW07361)验证,准确度和精密度均能达到环境监测分析的要求,为水系沉积物中重金属元素含量的测定提供了简单可靠的分析方法。  相似文献   

20.
以云南省昆明市东川主要河流及附近土壤、植物为研究对象,对其进行采样分析,并根据美国环境保护署(U.S.EPA)推荐健康风险评价方法对东川流域多种环境因素进行了重金属的健康风险评价。结果表明,水环境中致癌物质造成的风险最大,风险值在2.35×10^(-4)~8.27×10^(-4),达到U.S.EPA推荐的最大值10^(-4),植物根部的健康风险值为0.40×10^(-1)~7.00×10^(-1),茎叶部分的风险值为2.42×10^(-2)~15.24×10^(-2),根部存在的重金属对人体的健康风险约为茎叶部分的5倍;土壤中非致癌物质的健康风险影响较大,总健康风险值区间为0.64×10^(-1)~3.83×10^(-1)。评价结果可为该区域地表水、土壤和植物资源的污染治理、保护开发提供依据。  相似文献   

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